Private equity firm KKR & Co LLP said on Wednesday that it is investing $90 million in Savant Systems, a company that helps control the lighting, temperature and TVs in some of the world’s wealthiest homes. The private company, which is valued at roughly $200 million following this round of funding, was founded in 2005 by engineer and tech entrepreneur Robert Madonna. It sells home automation systems to the luxury market and can be found in homes of tech CEOs and musicians, said Chief Executive Officer William Lynch in an interview. Lynch, the former CEO of Barnes & Noble, said in an interview that the company had been looking to raise capital from investors before choosing KKR, which will take a roughly 35 percent stake.